chemistry module 2 smart book (early ideas about matter) and (defining the atom)
Aristotle did not believe that __________ _____________ could exist
empty space
matter is made of earth, air, fire, and water -WHO
Aristotle
What name is given to John Dalton's ideas about matter, which resulted from many careful measurements and observations?
Dalton's atomic theory
True or false: Democritus's ideas were rejected, in part, because the experiments he performed refuted his claims.
False
It was not until nearly 1900 that scientists began to be able to answer questions about the composition of the
atom
Radiation that originates from the cathode and travels to the anode of a cathode-ray tube is called a
cathode ray
Which is radiation that originates from the cathode and travels to the anode of a cathode-ray tube
cathode ray
When did scientists begin to be able to answer questions about the composition of the atom
late 1800's
J.J. Thomson's cathode-ray tube experiments in the late 1890s were designed to determine the ratio of an electron's _______________ to its _______________
mass, charge
Dalton's atomic theory explains the law of conservation of mass because, according to the theory, ___________
the number of atoms of each type is the same before and after a reaction
cathode-ray tube
what is this
1) In a chemical reaction, atoms are separated, combined, or rearranged 2) Atoms are indivisible and indestructible 3) Atoms of a specific element are different from those of another element
part of Dalton's atomic theory?
...
...
Which statements about the ideas of Democritus, Aristotle, and Dalton are true? (3)
1) Aristotle did not accept Democritus's ideas because he did not believe that empty space could exist 2) Both Dalton and Democritus proposed that matter is composed of extremely small particles 3) Aristotle believed that matter was made up of earth, air, fire, and water
Democritus's ideas were not accepted at the time he proposed them (or for thousands of years afterward) because (3)
1) Science as we know it did not exist 2) Aristotle, one of the most influential Greek Philosophers, did not support them 3) he was unable to back up his ideas with evidence from controlled experiments
Several thousand years ago, people sought after the truth about the nature of matter by __________(2)
1) formulating explanations based on life experiences 2) thinking intellectually
Democritus proposed (3)
1) matter was not infinitely divisible 2)matter was made up of tiny particles called atomos (atoms) 3) the atoms that made up matter could not be created, destroyed, or further divided
Democritus proposed that (3)
1) the atoms that made up matter could not be destroyed, or further divided 2) matter was not infinitely divisible 3) matter was made up of tiny particles called atomos (atoms)
Many early philosophers concluded that matter (2)
1) was composed of earth, water, air, and fire 2) Could be endlessly divided into smaller and smaller pieces
A cathode-ray tube (3)
1. depends on the use of a vacuum pump for its function 2. was used to study the relationship between mass and charge 3. has metal electrodes connected to opposite ends
Different atoms combine in simple whole-number ratios to form compounds -WHO
Dalton
Matter is made up of tiny particles that are indestructible and indivisible - WHO (2)
Dalton and Democrtius
John Dalton's ideas about matter, which arose from his many experiments in which he studied the mass ratios of elements involved in chemical reactions, are collectively known as ______________ ____________ ____________ (3)
Dalton's atomic theory
The smallest particle of an element that retains the properties of the element is called a
atom
What is the smallest particle of an element that retains the properties of the element?
atom
According to Dalton's atomic theory
atoms are separate, combined, or rearranged in a chemical reaction
Through his oil-drop experiments, Millikan was able to determine the ____________ and ___________ of an electron
charge, mass
Democritus proposed that matter was made up of atoms, which could not be __________ , ____________, or further destroyed
created destroyed
Dalton's atomic theory supports the law of conservation of mass because in his theory, atoms are not created, _____________ , or divided in a chemical reaction. Therefore, the total ______________ before and after the reaction does not change
destroyed mass
several thousand years ago, science as we know it today_____________
did not exist
Thomson's cathode ray-tube experiments led to the discovery of which subatomic particle
electron
A negatively charged, fast-moving particle with an extremely small mass that is found in all forms of matter and moves through the empty space surrounding an atom's nucleus is called a
electrons
Aristotle believed that
matter was made up of earth, fire, air, and water
